纳米SiO_2对不同强度等级混凝土性能的影响  

Influence of Nano-SiO_2 on Performance of Different Strength Grade Concrete

作　　者：陈安生 唐小萍 

机构地区：[1]湖南高速铁路职业技术学院,衡阳421001

出　　处：《硅酸盐通报》2013年第8期1521-1527,共7页Bulletin of the Chinese Ceramic Society

基　　金：湖南省科技厅科研计划项目(2010GK3148);湖南省教育厅科研计划项目(10CO159)

摘　　要：通过纳米SiO2与粉煤粉复掺，用纳米SiO2等量替换水泥，分别配制强度等级为C35的普通混凝土和强度等级为C60的高强混凝土，对混凝土试件进行主要性能测试。结果表明28d龄期立方体抗压强度、轴心抗压强度、弹性模量在纳米SiO2掺量为2％～3％范围内取最大值，对C35级别与C60级别的试件28d龄期的力学性能影响为：立方体抗压强度最大增幅分别为14％、10％；轴心抗压强度最大增幅分别为18％、14％；弹性模量最大增幅分别为17．5％、11．2％。混凝土的工作性随纳米SiO2掺入量的增加均呈快速降低趋势，相同纳米SiO2掺量的混凝土1235级别的坍落度和扩展度下降速度比C60级别的更快。混凝土的抗渗性能随纳米SiO2掺入量的增加而提高，低强度等级的抗渗透能力的提高幅度明显高于较高强度等级的混凝土。Mixed the nano-SiO2 with fly ash, used the Equivalent amount of nano-SiO2 to take place of cement, deployed grade C35 ordinary concrete and grade C60 high strength concrete respectively, tested the major performance of the concrete specimens. The results showed that cube compressive strength, axial compressive strength, modulus of elasticity got the maximum value when the ratio of nano- SiO2within the range of 2% to 3% in 28 d age. The influence of that to the mechanical properties of grade C35 specimen and grade C60 specimens respectively in 28 d age is： cube compressive strength maximally increased 14% and 11%, axial compressive strength maximally increased 18% and 14%, modulus of elasticity maximally increased 17.5% and 11.2% respectively. The workability of concrete showed decreased rapidly with the increase of the contents of concrete . Grade C35 concrete decreased faster than the grade C60 concrete in slump and divergence with the same content of nano-SiO2. The impervious performance of concrete improved with the increasing of the amount of nano-SiO2. The increased range of the impermeability ability of the low strength grade concrete apparently higher than the higher strensth grade concrete.

关 键 词：纳米SIO2 强度等级 混凝土 性能 

分 类 号：TU528[建筑科学—建筑技术科学]